Thursday, July 2, 2009

The EURATOM project SUMO

I came across a European power point presentation that listed remaining technology issues before MSR development can begin. I copied the notes from the presentation, although I realize that this might not be for everyone.

Introduction: MSR remaining issuesA modified Ni-base alloy that is immune to Te-attack must be selected and its compatibility with fuel salt demonstrated; means for giving it adequate resistance to radiation damage must be found.

A method of intercepting and isolating tritium to prevent its passage into the steam system must be demonstrated.

Various steps in the processing system must be demonstrated and then be combined in an integrated system.

Graphite elements that are suitable for the MSR should be purchased (radiation behavior, graphite sealing).

On-line chemical analysis devices will be needed for the reactor and processing plant.Components and systems for reactor must be developed and tested.

The development and commercialization of a fluid fuel MS technology and its use in reactor concepts is a major challenge. However, the interest in advanced reactors for breeding and waste management is creating the incentives to develop this family of technologies.Preliminary consideration of environmental effects indicate that MOSART system could have attracted performance, good safety features and TRU transmutation efficiency while providing lower total materials inventories and waste compared to prior MSR designs.While a substantial R&D effort would be required to commercialize MOSART, there are no killing unresolved issues in the needed technology. The major technical uncertainties in the conceptual design are in the area of tritium confinement, fuel salt processing and behavior of some fission products.

The mission of ISTC # 3749 is to test and select molten salts and metallic structural materials, which will operate successfully under the conditions of promising nuclear energy applications.The work in ISTC # 3749 will be focused on Th-fuelled system to produce energy in a competitive way (in co-operation with FP6 ALISIA project and FP7 SUMO proposal).Experimental effort will be placed on evaluation of the potential of advanced molten salt fluorides mixtures for pyrochemistry partitioning application (in co-operation with FP7 ACSEPT project).

Expected developments

WP 1: Choice of molten salt compositions for detailed studies; Special attention will be given to the following fuel solvent systems: Li,Th/F, Li,Be,Th/F, Li,Ca,Ba/F, etc.

WP 2, WP 3Target: This work group will focus on the experimental study of physical and chemical properties of molten salt mixtures. Starting from LiF-containing systems, composition will be optimised with respect to margin to freezing, An/Ln solubility, adequate transport properties, rare earths removal and An/Ln separation on the basis of possible addition of other components: ThF4 and BeF2 or CaF2 and BaF2. As fissile components UF4 and PuF3 will be considered.

An important requirement for such a program is the availability of experimental facilities for handling of fluoride salts, which is guaranteed by the participation of RRC-KI, IHTE and VNIITF. The chemical and physical properties of the candidate salts will be established based on a variety of experiments and evaluations that will be performed at the participating institutes.

Target: The main objective of this group is, to select structural materials, which will operate successfully under the required conditions. The major achievements will be: (1) ability to produce and maintain a high level of purity in fuel salt, (2) effective control of the redox potential of the fuel salt in order to minimize corrosion, (3) understanding of basic corrosion mechanisms in systems with temperature gradient, (4) improved materials development and testing as applied to conditions of reference designs.

The long-term behavior of materials will be comparatively investigated by performing exposure tests in fuel salt, defined on the basis of the results obtained in previous section and that should be representative of the nominal operating conditions.

The changes in the alloy microstructure will be studied. The specific corrosion resistance of welds and the influence of the surface state will be examined. The stability of the mechanical properties after exposure will be also verified.